1. Field of the Invention
The present invention is directed to an electronic component, particularly a surface acoustic wave (SAW) component, of the type having a piezoelectric substrate with electrically conductive structures arranged thereon, and having a base plate with external electrical terminal elements that are electrically connected to the conductive structures of the chip.
2. Description of the Prior Art
Electronic components of the above type usually have chips with a piezoelectric substrate and with electrically conductive structures arranged on the substrate, particularly active filter structures such as, for example, interdigital transducers, terminal tracks, what are referred to as pads, and the like. The electrical contacting of these structures to external terminal elements in turn ensues via interconnects that are applied onto a carrier plate of the chip, for example onto a ceramic or plastic plate.
During the course of the continuously increasing miniaturization of the components, i.e. given further reduction of the dimensions of SAW components down to chip dimensions smaller than 3xc3x973 mm, the space required for the electrical contacting of the componentxe2x80x94which cannot be reduced to the same extentxe2x80x94causes considerable problems, particularly when the components are protected against physical and chemical environmental influences and moisture with a protective covering. Such a protective covering can be formed by multi-layer, usually 2-layer, structured protective filmsxe2x80x94also called PROTEC by Siemens Matsushita Components GmbH and Co. KG.
An object of the present invention is to create a solution that allows further miniaturization of the SAW components without the protective effect of the protective film and the efficiency of the contact elements and of the SAW components overall being degraded.
Given an electronic component of the type initially described, this object is inventively achieved in general by the demand for minimal chip dimensions being met by displacing the electrical contact elements into the plane above the protective film.
More specifically, this object is achieved in accordance with the invention in an electronic component having a piezoelectric substrate with electrically conductive structures arranged on the substrate and having a base plate with external electrical terminal elements that are electrically connected to the conductive structures of the chip, and wherein a structured protective film is applied onto the chip surface which carries the conductive structures, the surface of the protective film facing away from the piezoelectric substrate carrying stripe-shaped electrical contact elements which are directly connected to the electrically conductive structures via solder balls known as bumps, and are also connected to the electrical terminal elements of the base plate, without any crossovers.